You may have up to 4 Basic Pokémon cards in your deck with Unown in their names

Unown

60 HP

Shuffle
Once during your turn (before your attack), you may search your deck for another Unown and and switch it with Unown. (Any cards attached to Unown, damage counters, Special Conditions, and effects on it are now on the new Pokémon.) If you do, put Unown on top of your deck. Shuffle your deck afterward. You can't use more than 1 Shuffle Poké-Power each turn.

Hidden Power
Search your deck for up to 3 different types of basic Energy cards, show them to your opponent, and put them into your hand. Shuffle your deck afterward.